According to a notice [PDF] posted with the National Highway Traffic Safety Administration, a manufacturing issue may cause the vehicle’s relay system, which controls the secondary air injection pump, to fail.

If this condition were to occur, the “check engine” warning light will illuminate, and the pump could continuously operate, overheat, and melt causing odor or smoke to occur and possibly, fire.

Subaru tells NHTSA that it first became aware of the issue in 2011 when its supplier received an initial technical report of “check engine” warning light illumination due to secondary air injection pump failure. There was no fire associated with the incident.

Between April 2011 and Sept. 2013, the supplier investigated and determined the root cause for the check engine warning light illumination was insufficient contact point pressure of the relay associated with the secondary air injection pump. At this point, the supplier decreased the contact pressure in an attempt to remediate the issue.

However, in Oct. 2013, the company received the first report of an air injection pump emitting smoke and catching fire. A second report was received in May 2015.

Between then and Sept. 2016, an investigation team collected parts from vehicles involved in similar incidents and ultimately determined that a product safety recall was needed.

Subaru will notify owners, and dealers will replace the secondary air injection pump relay.